OECD Environmental Outlook to 2050: Part two

The OECD Environmental Outlook to 2050 notes the following trends in biodiversity, water and health:

Biodiversity

By 2050, without new policies…

Globally, terrestrial biodiversity is projected to decrease by a further 10% by 2050, with significant losses in Asia, Europe and Southern Africa.

Mature forests are projected to shrink by 13%.

The main pressures driving biodiversity loss include land-use change (e.g. agriculture), the expansion of commercial forestry, infrastructure development, human encroachment and fragmentation of natural habitats, as well as pollution and climate change.

Approximately one third of freshwater biodiversity has already been lost, and further loss is projected to 2050.

If action is taken…

Globally, the number and size of protected areas have increased and now account for nearly 13% of the global terrestrial area. However, temperature grasslands, savannas, shrublands and marine ecosystems are poorly represented and only 7.2% of territorial seas are designated as Marine Protected Areas.

Outlook simulations suggest that in order to reach the 17% terrestrial target agreed under the Convention on Biological Diversity, a further 9.8 million km2 of land would need to be protected.

If climate mitigation options do not rely heavily on expanding land use for biofuels, this would cut cumulative deforestation emissions by 12.7 GtC and contribute to 7% of the required emission reduction to 2050. At the same time, biodiversity would be protected through a reduction in the extent of cropland by 1.2 million km2, and 1 million km2 less land for animal grazing by 2050 relative to the Baseline.

Water

By 2050, without new policies…

Freshwater availability will be further strained, with 2.3 billion more people than today (in total over 40% of the global population) projected to be living in river basins under severe water stress, especially in Africa and Central Asia.

Global water demand is projected to increase by 55%, due to growing demand from manufacturing (+400%), thermal electricity generation (+140%) and domestic use (+130%). In the face of these competing demands, there will be little scope for expanding irrigation water use under this scenario. The main increases in water demand will be in emerging economies and developing countries.

The number of people with access to an improved water source (although not necessarily safe water for human consumption) is expected to increase, primarily in the BRIICS (Brazil, Russia, India, Indonesia, China, South Africa). However, globally more than 240 million people are expected to be without such access by 2050.

Overall, the Millennium Development Goal (MDG) of halving by 2015 the 1990 level of the population without access to an improved water source is expected to be met, but not in some key regions (such as Sub-Saharan Africa).

The MDG for sanitation will not be met by 2015; by 2050 1.4 billion people are projected to still be without access to basic sanitation.

Health and environment

By 2050, without new policies…

Air pollution is set to become the world’s top environmental cause of premature mortality, overtaking dirty water and lack of sanitation. Air pollution concentrations in some cities, particularly in Asia, already far exceed Work Health Organisation safe levels, and they are projected to deteriorate further to 2050.

The number of premature deaths from exposure to particulate matter (PM) (which leads to respiratory failures) is projected to more than double worldwide, from just over 1 million today to nearly 3.6 million/y in 2050, with most deaths occurring in China and India.

According to the OECD, the absolute number of premature deaths from exposure to ground-level ozone is to more than double worldwide (from 385 000 to nearly 800 000) between 2010 and 2050. Most of these deaths are expected to occur in Asia. However, once adjusted to the size of the population, OECD countries – with their ageing and urbanized populations – are likely to have one of the highest rates of premature death from ground-level ozone, second only to India.

Substantial increases in sulphur dioxide and nitrogen oxides emissions are likely to occur in the key emerging economies in the coming decades. Compared to the year 2000, emission levels of SO2 are projected to be 90% higher and NOx 50% higher in 2050.

Today, only 2% of the global urban population are living with acceptable PM10 concentrations (below the WHO Air Quality Guideline of 20 µg/m3). In 2050, the Baseline scenario projects that the percentage of people living in cities with concentrations above the highest WHO target of 70 µg/m3 will be even higher in all regions. This is despite the air quality improvements to 2050 in OECD and the BRIICS, as these improvements are expected to be eclipsed by population growth in urban areas.

Disease related to exposure to hazardous chemicals is significant worldwide, but more severe in non-OECD countries where chemical safety measures are still insufficient. Yet, non-OECD countries are projected to greatly increase chemicals production, with the BRIICS overtaking the OECD in global sales by 2050 under the Baseline. While OECD governments are making progress in assessing human exposure to chemicals, knowledge of the health impacts is still limited.